* Fix BUG#19217 "dict_load_indexes() may read the delete-mark incorrectly".
 * Remove obsolete and unused variables from srv0srv.c.
 * Remove srv_sys->operational since it is unused.
 * Make thread_id parameter in os_thread_create() optional.
 * Add platform-specific os_thread_ret_t and OS_THREAD_DUMMY_RETURN,
   and convert thread start functions to use them.


storage/innobase/dict/dict0dict.c:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/dict/dict0load.c:
  Applied innodb-5.1-ss492 snapshot.
   dict_load_indexes(): pass comp=0 to rec_get_deleted_flag(), because
   SYS_INDEXES always is in ROW_FORMAT=REDUNDANT (Bug #19217).
storage/innobase/include/os0thread.h:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/include/srv0srv.h:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/include/trx0roll.h:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/include/univ.i:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/log/log0recv.c:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/os/os0thread.c:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/que/que0que.c:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/srv/srv0srv.c:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/srv/srv0start.c:
  Applied innodb-5.1-ss492 snapshot.
storage/innobase/trx/trx0roll.c:
  Applied innodb-5.1-ss492 snapshot.